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1.
Micromachines (Basel) ; 14(8)2023 Aug 20.
Article in English | MEDLINE | ID: mdl-37630181

ABSTRACT

The temporomandibular joint (TMJ) is a critical joint for the opening and closing of the mouth. The generation of customised TMJs according to individuals' dental anatomy is needed. Currently, the implants available on the market lack consideration of the patient's dental anatomy. This leads to the creation of an imbalance in the reaction forces on both ends of the TMJ. This requires a slight structural change in the design parameters to give a solution. The purpose of this study is to propose a new design that includes the geometry and materials for a TMJ implant. Stress analysis was carried out on the TMJ to balance the reaction forces at both TMJ ends. A static analysis was performed using ANSYS Workbench, to compare the results of two customised designs of TMJ implants, in order to better balance the reaction forces at both ends. The model in the study showed that the reaction forces for both the patient-specific TMJ implants were nearly balanced. The reaction forces were better balanced, and almost equivalent to the intact conditions. The stresses in the mandible were more uniformly distributed in the customised design of the TMJ implant. The two types of design showed that the custom design took up less space in the patient's region of surgery, making it a better option compared to a stock TMJ implant. The custom implant would allow faster patient rehabilitation, as the reaction forces would be close to those in intact conditions.

2.
Rev. bras. cir. cardiovasc ; 37(4): 511-516, Jul.-Aug. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1394735

ABSTRACT

Abstract Introduction: In developing countries like India, it is common for late presentation of Tetralogy of Fallot (TOF) patients to a hospital as compared to that of developed countries. The objective of this study is to analyze the surgical outcome of TOF patients with age > 15 years. Methods: This is a retrospective descriptive study of the surgical outcomes of 45 adult patients undergoing correction for TOF. Epidemiology, symptomology, and preoperative evaluation were performed. Results: Most of the patients were male (33 [73%]). The median age was 21 years. A total of 42 (93.33%) patients had subaortic ventricular septal defect (VSD), while three (6.6%) patients presented with doubly committed VSD. The most common type of right ventricular outflow tract (RVOT) obstruction was combined infundibular and valvular types, accounting for 34 cases (75.5%). Six patients had infundibular RVOT obstruction, while three patients (6.6%) had predominantly valvular pulmonary stenosis. We performed trans-right atrial repair in 33 patients. Right atrium-pulmonary artery approach was used in five patients (11.1%). The most common postoperative complication was right bundle branch block, seen in 14 patients, with a mortality rate of 2% in the early postoperative period. We achieved excellent early and midterm survival results and significant improvement in functions and disease-free quality of life. Conclusion: Intracardiac repair in adult TOF can be performed with low mortality, less residual RVOT obstruction, and need for revision of RVOT far less frequent by using the Jhajhria Infundibular Resection Adequacy Assessment technique (JIRAAT) to assess for adequacy of infundibular resection.

3.
Braz J Cardiovasc Surg ; 37(4): 511-516, 2022 08 16.
Article in English | MEDLINE | ID: mdl-35072397

ABSTRACT

INTRODUCTION: In developing countries like India, it is common for late presentation of Tetralogy of Fallot (TOF) patients to a hospital as compared to that of developed countries. The objective of this study is to analyze the surgical outcome of TOF patients with age > 15 years. METHODS: This is a retrospective descriptive study of the surgical outcomes of 45 adult patients undergoing correction for TOF. Epidemiology, symptomology, and preoperative evaluation were performed. RESULTS: Most of the patients were male (33 [73%]). The median age was 21 years. A total of 42 (93.33%) patients had subaortic ventricular septal defect (VSD), while three (6.6%) patients presented with doubly committed VSD. The most common type of right ventricular outflow tract (RVOT) obstruction was combined infundibular and valvular types, accounting for 34 cases (75.5%). Six patients had infundibular RVOT obstruction, while three patients (6.6%) had predominantly valvular pulmonary stenosis. We performed trans-right atrial repair in 33 patients. Right atrium-pulmonary artery approach was used in five patients (11.1%). The most common postoperative complication was right bundle branch block, seen in 14 patients, with a mortality rate of 2% in the early postoperative period. We achieved excellent early and midterm survival results and significant improvement in functions and disease-free quality of life. CONCLUSION: Intracardiac repair in adult TOF can be performed with low mortality, less residual RVOT obstruction, and need for revision of RVOT far less frequent by using the Jhajhria Infundibular Resection Adequacy Assessment technique (JIRAAT) to assess for adequacy of infundibular resection.


Subject(s)
Heart Septal Defects, Ventricular , Tetralogy of Fallot , Adolescent , Adult , Female , Heart Septal Defects, Ventricular/surgery , Humans , Infant , Male , Quality of Life , Retrospective Studies , Tertiary Care Centers , Tetralogy of Fallot/surgery , Treatment Outcome , Young Adult
4.
Comput Methods Biomech Biomed Engin ; 25(11): 1262-1275, 2022 Aug.
Article in English | MEDLINE | ID: mdl-34939875

ABSTRACT

Conventionally biometals were used for design and development of bioimplants. However, the Young's Modulus (YM) of these bioimplants is higher than that of a natural bone. Asymmetric load transfer from a bone to the bioimplant results in aseptic loosening and stress shielding. Here-in, the use of functionally graded materials (FGM) has been introduced to design the femoral stem prosthesis as a model bioimplant using computational biomechanics. The material properties variations in these FGMs in longitudinal and radial directions are explored to minimize the aseptic loosening and stress-shielding that plays a vital role in defining the performance and longevity of the prosthesis. Three groups of FGM (Ti-HA, SS316L-HA and CoCr alloy-HA) have been explored to design the stem prosthesis and the finite element analysis (FEA) was carried out using computational biomechanics. The stress distribution profile in the designed stem prosthesis demonstrated an increase in the stress values with an increase in the volume fraction exponent. The results corroborated with the stress distribution obtained from the simulation results of a cortico-cancellous bone. The stress distribution in the Ti-HA prosthesis is observed to be more uniform than CoCr-HA and SS316L-HA prosthesis. In addition, the reduced number of stress shielding points were observed for the Ti-HA prosthesis when compared with the CoCr-HA and SS 316 L-HA stem prostheses. Hence, the results suggested that the Ti-HA prosthesis could be considered as a mechanically stable prosthesis and the same could offer safe design for further development of a femoral bioimplant.


Subject(s)
Hip Prosthesis , Elastic Modulus , Femur/surgery , Finite Element Analysis , Prosthesis Design , Stress, Mechanical
5.
J Food Sci Technol ; 58(8): 3205-3214, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34294983

ABSTRACT

Ultrafiltration and Diafiltration processes are used to concentrate proteins present in defatted milk in order to manufacture milk protein concentrate (MPC) powders. Selective passage of the water-soluble components causes retention as well as concentration of colloidal milk components in these processes. Increase in calcium and casein contents decreases the stability of milk proteins present in ultrafiltered retentates and negatively influence properties of manufactured MPC powders. Homogenization, diafiltration and disodium phosphate induced changes in properties of low-protein MPC powders were targeted in this study. Applied treatments significantly (P < 0.05) improved foaming and emulsification, solubility, viscosity, heat stability, dispersibility, specific surface area and buffer index of resultant MPC powders over control. Fresh, treated low-protein MPC powders showed significantly higher (< 0.05) solubility values over control sample, which remains higher even after 60 days of storage at 25 ± 1 °C. The rheological behaviour of reconstituted low-protein MPC solutions was also studied. It was best explained as Herschel-Bulkley rheological behaviour. Low-protein MPC powders with improved functional properties may find better use as a protein ingredient in different dairy and food applications.

6.
Comput Methods Biomech Biomed Engin ; 24(15): 1742-1751, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34097536

ABSTRACT

The development of prosthetic bioimplants for fracture fixation using curved bone plates has been used as an established procedure for treatment in orthopedic. Here-in, we propose a novel curved bone plate fixation strategy to fix the designed biocompatible plates in different fracture models. Various biocompatible metallic biomaterials such as Ti-alloy (Ti-6Al-4V), stainless steel (SS 316L), and Co-alloy (Co-Cr) were created in SOLID works and used for the design of the bone plates. The typical fracture models (transverse and oblique) were created over a standard femur bone (models created using Materialize MIMIC/MAGIC) and two bone plates of similar materials were fixed side-by-side over the fractured femur using the screws made from Ti-6Al-4V. The finite element analysis (FEA) was carried out to evaluate the interface deformation, stress, and strain generated at the bone-bioimplant interface. The results from FEA demonstrated that the interface deformation and stress for a bone-bioimplant assembly are significantly reduced when natural anisotropic condition (functionally graded materials properties) of the human femur was well considered. Based on the analysis, Ti-6AL-4V and SS 316L were found as the best fit metallic biomaterials for the design and development of bone plate prosthetic bioimplants for fixation of an oblique fracture and transverse fracture respectively.


Subject(s)
Bone Plates , Femoral Fractures , Alloys , Femoral Fractures/surgery , Femur/diagnostic imaging , Femur/surgery , Finite Element Analysis , Humans , Titanium
7.
Asian J Neurosurg ; 16(4): 725-731, 2021.
Article in English | MEDLINE | ID: mdl-35071069

ABSTRACT

INTRODUCTION: In this double-blinded randomized controlled trial, we compare the long-term clinicoradiological effects of anterior cervical discectomy and fusion with polyether ether ketone implant (ACDF with PEEK) versus artificial cervical disc (cervical disc arthroplasty [CDA]) in patients with single and bilevel cervical degenerative disc disease (CDDD). AIMS: We aimed to compare the pain scores, cervical kinematics, and radiological outcomes in patients undergoing CDA and ACDF for single and bilevel CDDD over 5 years. SETTINGS AND DESIGN: This study was carried out from 2010 to 2019 in the Neurosurgery Department of a Tertiary Care Hospital attached to a Medical College in India. SUBJECTS AND METHODS: We enrolled 30 patients in each group. Clinical and radiological assessments were carried out for all patients over a period of 5 years. STATISTICAL ANALYSIS USED: Wilcoxon Signed-rank test, Mann-Whitney U-test, and Fischer's exact test were used for comparing the preoperative and follow-uP values. R software version 3.6.0 was used for statistical analysis. RESULTS: A significant improvement in the cervical range of motion, sagittal range of motion (ROM), and functional spinal unit (FSU) was observed in the CDA group at final follow-up, while the PEEK group reported a significant decrease in the ROM and FSU and the difference between the two groups was also found to be statistically significant. CONCLUSIONS: When assessed over 5 years following surgery, we found CDA to be superior with respect to ROM, FSU, overall cervical alignment, and maintenance of disc height when compared to ACDF with PEEK implant.

8.
J Environ Manage ; 275: 111249, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32836169

ABSTRACT

Lagooning sludge (LS), which is used as soil amendment in Morocco, may contain microplastics (MPs). The aim of this study was to examine the effect of dewatering and co-composting of LS with green waste (GW) on the MPs' evolution. In this context the present study proposes fast-preliminary steps to detect plastics in lagooning sewage sludge before the extraction and identification process. We used pyrolysis GC/MS spectrometry to investigate the presence of chemical compounds possibly derived from plastics, and fluorescence staining by Nile Red to detect fluorescent particles suspected as plastics. Thereafter, we quantified the MPs particles after density fractionation and investigated their nature by Raman spectroscopy. RESULTS: indicated the presence of an average of 40.5 ± 11.9 × 103 MPs particles/kg (dry matter) and 36 ± 9.7 × 103 MPs particles/kg (dry matter) in fresh sludge and dewatered sludge respectively. Sludge dewatering in drying beds resulted a loss of small MPs (<500 µm). In co-composts, the quantity of MPs varied with the proportion of sewage sludge. The distribution of MPs types differentiated by colour and types (polypropylene, polyethylene, polyamide and polyester) evolved differently. Conventional co-composting did not have any effect on MPs quantity, indicating that they are not biodegradable under these temperature conditions, but it influenced their particle size. The risks of these pollutants after repeated field application and the possibility of their reduction through others co-composting procedures and techniques would be further investigated.


Subject(s)
Composting , Sewage , Microplastics , Morocco , Plastics , Pyrolysis , Spectrum Analysis, Raman , Staining and Labeling
9.
J Food Sci Technol ; 56(3): 1622-1630, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30956343

ABSTRACT

Concentration of milk proteins by ultrafiltration (UF) and diafiltration (DF) processes during manufacturing of milk protein concentrate (MPC) powders alter their natural milk protein stabilization system. Increasing calcium and protein contents often leads to poor functional properties in MPC powders. The pH adjustment using disodium phosphate (DSP, Na2HPO4) and DF with 150 mM NaCl solution of UF retentate were hypothesized to produce desirable changes in various properties of resulted MPC powders. Addition of Na2HPO4 followed by homogenization; DF of 5 × UF retentate with 150 mM NaCl solution resulted in significant improvement in the dispersibility, wettability, flowability, solubility, heat stability, buffer index, emulsification and foaming and water and oil binding capacities of the MPC powders. The solubility of developed MPC powders was significantly higher than MPC-C powder in fresh as well as even after 90 days of storage at 25 ± 1 °C. Rheological behaviour of reconstituted MPC was best explained by Herschel Bulkley model. Scanning electron microscopy micrograph indicated that MPC powders were having smooth surfaced, intact and separate smaller particles compared to rough, larger, infused aggregates with dents in MPC-C. Technological interventions applied are easier to adopt, cost-effective and efficient in producing excellent quality MPC powders that may find applications in wide range of novel food formulations.

11.
J Food Sci Technol ; 55(9): 3526-3537, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30150811

ABSTRACT

Poor solubility of milk protein concentrate (MPC) powders are attributed to their high protein and calcium contents. Concentration of skim milk in ultrafiltration (UF) and diafiltration (DF) increased total solids, protein and mineral contents and changed pH and ζ-potential values of the retentates that leads to milk proteins destabilization in 7× UF/DF retentates. Hence, this investigation was aimed to study the effect of change in pH of skim milk (no change; native pH maintained) and DF retentates (5.85 and 7.10) with KOH, NaOH and NaH2PO4∙2H2O on physicochemical, reconstitution, functional and rheological properties of fresh MPC70 powders. MPC70-7.10 powder had significantly higher (P < 0.05) solubility, but MPC70-NaOH and MPC70-5.85 showed significantly lower solubility than control. However, after two months storage at 25 ± 1 °C, control powder had significantly lower solubility (27.78% decrease) than treated powders. These changes in pH, significantly decreased calcium content and specific surface area; significantly improved viscosity, water binding, oil binding, emulsifying, foaming and buffering capacities, L*, a*, flowability, pH (except MPC70-5.85) and packed bulk density (except MPC70-NaOH) of treated powders over control. However, rennet coagulation time of all reconstituted powder solutions was similar. Hershel Bulkley, a best fit model, efficiently explained the pseudoplastic rheological behavior of all reconstituted MPC70 powders. This investigation had established that change in pH could improve the functional properties of MPC70 powders and is a simple, cheap, compatible and easy to use approach. Treated MPC70 powders could replace control in several food formulations owing to their improved functional properties.

12.
J Food Sci Technol ; 55(4): 1376-1386, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29606752

ABSTRACT

Poor solubility is the major limiting factor in commercial applications of milk protein concentrates (MPC) powders. Retentate treatments such as pH adjustment using disodium phosphate (Na2HPO4), also responsible for calcium chelation with homogenization and; its diafiltration with 150 mM NaCl solution were hypothesized to improve the functional properties of treated MPC70 powders. These treatments significantly improved the solubility, heat stability, water binding, dispersibility, bulk density, flowability, buffer index, foaming and emulsifying capacity of treated powders over control. Rheological behaviour of reconstituted MPC solutions was best explained by Herschel Bulkley model. Compared to rough, large globular structures with dents in control; majorly intact, separate, smaller particles of smooth surface, without any aggregation were observed in SEM micrograph of treated powders. Applied treatments are easy, cost-effective and capable to improve functional properties of treated powders that could replace control MPC70 powder in various food applications where protein functionality is of prime importance.

13.
J Food Sci Technol ; 55(5): 1648-1655, 2018 May.
Article in English | MEDLINE | ID: mdl-29666517

ABSTRACT

Studied the effect of culture (2, 2.5 and 3%), ultrafiltered (UF) retentate addition (0, 11, 18%), total milk solids (13, 13.50, 14%) and heat treatments (80 and 85 °C/30 min) on the change in pH and titratable acidity (TA), sensory scores and rheological parameters of yoghurt. With 3% culture levels, the required TA (0.90% LA) was achieved in minimum 6 h incubation. With an increase in UF retentate addition, there was observed a highly significant decrease in overall acceptability, body and texture and colour and appearance scores, but there was highly significant increase in rheological parameters of yoghurt samples. Yoghurt made from even 13.75% total solids containing nil UF retentate was observed to be sufficiently firm by the sensory panel. Most of the sensory attributes of yoghurt made with 13.50% total solids were significantly better than yoghurt prepared with either 13 or 14% total solids. Standardised milk heated to 85 °C/30 min resulted in significantly better overall acceptability in yoghurt. Overall acceptability of optimised yoghurt was significantly better than a branded market sample. UF retentate addition adversely affected yoghurt quality, whereas optimization of culture levels, totals milk solids and others process parameters noticeably improved the quality of plain set yoghurt with a shelf life of 15 days at 4 °C.

15.
J Food Sci Technol ; 54(6): 1678-1688, 2017 May.
Article in English | MEDLINE | ID: mdl-28559627

ABSTRACT

Ultrafiltration and diafiltration of skim milk altered delicate salt equilibrium and composition of 5× UF retentate (5× UFR), and thus adversely affected the reconstitutional and functional properties of milk protein concentrate (MPC) powders. It might be due to interaction and aggregation of proteins during spray drying. Therefore, this study was envisaged to investigate the effect of disodium phosphate (DSP) addition, diafiltration and homogenization of retentates on physico-chemical, functional and rheological properties of MPC60 powders. Solubility of fresh control powder was significantly lower than MPC60-H powder; at par with that of MPC60-DSP and MPC60-Na-K, but remained minimum after 60 days of storage at 25 ± 1 °C. The pH (6.6) adjustment of 5× UFR with DSP, significantly enhanced the dispersability, wettability, specific surface area (SSA), heat coagulation time (HCT), emulsification capacity and stability; buffer index of MPC60-DSP powder over control. Diafiltration of 5× UFR with NaCl and KCl, significantly (P < 0.05) decreased calcium content, but enhanced pH and mineral content of MPC60-Na-K powder. This treatment led to significant improvement in dispersability, SSA, emulsification capacity and stability, HCT and oil binding properties. Flowability, wettability, dispersability, HCT, foaming capacity, emulsification capacity and stability were also improved significantly in MPC60-H powder made from homogenized 5× UFR. Rheological behavior of reconstituted powder samples exhibited pseudoplastic behavior, best explained by Hershel Bulkley model. These MPC60 powders with improved functional properties can be used for the improvement of quality attributes of various food formulations.

16.
19.
J Food Sci Technol ; 51(9): 1737-49, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25190829

ABSTRACT

This study was conducted to evaluate the efficacy of purified free and immobilized xylanase in enrichment of fruit juices. Extracellular xylanase produced from Bacillus pumilus VLK-1 was purified to apparent homogeneity by 15.4-fold with 88.3 % recovery in a single step using CM-Sephadex C-50. Purified xylanase showed a single band on SDS-polyacrylamide gel with a molecular mass of 22.0 kDa. The purified enzyme was immobilized on glutaraldehyde-activated aluminum oxide pellets and the immobilization process parameters were optimized statistically through response surface methodology. The bound enzyme displayed an increase in optimum temperature from 60 to 65 ºC and pH from 8.0 to 9.0. The pH and temperature stability of the enzyme was also enhanced after immobilization. It could be reused for 10 consecutive cycles with 58 % residual enzyme activity. The potential of purified xylanase (free and immobilized) in juice enrichment from grape (Vitis amurensis) and orange (Citrus sinensis) pulps has been investigated. The optimization of this process using free xylanase revealed maximum juice yield, clarity and reducing sugar on treatment with 20 IU/g fruit pulp for 30 min at 50 ºC. Treatment of both the fruit pulps with xylanase under optimized conditions resulted in an increase in juice yield, clarity, reducing sugars, titratable acidity, and filterability but a decline in turbidity and viscosity. Immobilized enzyme was more effective in improving juice quality as compared to its soluble counterpart. The results showed B. pumilus VLK-1 xylanase, in both free and immobilized form, as a potential candidate for use in fruit juice enrichment.

20.
J Food Sci Technol ; 51(9): 1956-64, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25190851

ABSTRACT

A study was conducted to develop good quality medium fat liquid dairy whitener from buffalo milk employing ultrafiltration (UF) process. The buffalo skim milk was UF concentrated to 4.05 to 4.18 (23.63 ± 0.30 % TS) fold and standardized to 10 % fat (on Dry Matter Basis) (i.e. formulation) and homogenized at 175.76 kg/cm(2). The addition of 0.4 % mixture of monosodium and disodium phosphate (2:1 w/w) improved the heat stability of homogenized formulation to an optimum of 66 min. The bland flavour of homogenized formulation with added 0.4 % mixture of monosodium phosphate and disodium phosphate (2:1 w/w) and 18 % sugar (on DMB) (i.e. medium fat liquid dairy whitener) was improved significantly (P < 0.01) with the addition of 0.2 % potassium chloride, but heat stability of medium fat liquid dairy whitener got reduced substantially (i.e. 19 min). With subsequent heat treatment to 85 °C for 5 min, heat stability of medium fat liquid dairy whitener got improved to reasonable level of 27 min. Whitening ability in terms of L* value of medium fat liquid dairy whitener in both tea and coffee was significantly (P < 0.01) better when homogenized at 175.76 kg/cm(2) vis-à-vis 140.61 kg/cm(2). Standardized medium fat liquid dairy whitener had significantly (P < 0.01) greater protein content (i.e. approximately 2.43 times) compared to market dairy whitener samples. At 2 % solids level, standardized medium fat liquid dairy whitener in tea/coffee fetched significantly (P < 0.01) better sensory attributes and instrumental whitening ability compared to market sample at 3 % solids level. There could be clear 33 % solids quantity saving in case of developed product compared to market dairy whitener sample.

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